Electromagnetically-controlled switch.



'A. S. GUBITT. ELEOTROMAGNETIOALLY CONTROLLED SWITCH.

APPLICATION FILED MAR. 30, 1908.

Patented Jun 15, 1909.

UNITED STATES PATENT OFFICE. ARGHIBALD s. OUBITT, OE scHENEOTAnr, NEW YORK, ASSIGNOR TO GENEEAL ELEOTEIG COMPANY, A CORPORATION O NEW YORK.

ELECTROMAGNETICALLY-CONTROLLED SWITCH. I

Specification of Letters Patent.

recanted June 15, 1909.

Application filed March so, .1905. Serial No. 424,047.

- particularly theprovision of means whereby the operation of a switch may be retarded through a certain interval of time after the energization of the coil by which it is controlled.

The necessity for retarding the operation of an electro-magnetically controlled'switch after energization of itscontrol circuit has out resistance in the motor circuit.

arisen Farticularly in connection with s stems 0 motor control in which a plurality of electro-magnetically operated switches Operate automatically in-succession to cut In such systems it is customary to provide a switch or relay which, after the operation of each resistance controlling switch, will temporarlly interrupt the actuating circuit ior the next succeeding switch and in this way prevent too rapid cutting out of resistance the motor circuit. The contacts of this relay and its actuatin coil are generally connectt ed in series in t e actuating circuit for the resistance controlling switches, and this relay 1n pullmg u therefore, interrupts its own circuit as we 1 as the actuating circuit leading to the coils of the resistance controlling switches. This "notchin called, is intended to pu up immediately after each resistance controlling switch op erates-and thus to prevent the next resistance switch from operating at once. It has been found necessary. in ractice to retard the operation of the note f g relay slightly in order to give the resistance controlling switches time to close before their actuating circuit is interrupted and for this purpose,

several arrangements ave been used, among others,- a lost-motion connection between the movable element of" the relay and the movable contact lifted by it. 5

- It is an object of my. invention toprovide electrically controlled means for retarding the movement of a relay or switch under the relay, as it is.

above described conditions, or under any without dep'artin from its spirit.- For in-.

stance, although, have shown myinvention as applied to what may be called a' purelytime limit relay, it may equally well be used in connection with a relay provided with a coil intended to carry motor current and thereby hold the relay up if when it has opierated the motor current exceeds a certain va ue.

Referring tothe drawing, Figure 1 is a front elevation of a switch or relay having my invention applied thereto; and Fig. 2 is a detail view, partly in section, of the same.

-In the drawing, thesWitch or relay in which my invention is embodied is shown as mounted upon a back late 1 of any suitable insulating material. he iron frame 2 of the relay is supported on'the plate 1' in any suitable. way, and within this frame is mounted a coil of wire 3 wound and'insulated in any wellknown' manner. This coil 3 serves as the actuating coil of the 'switch. Passing through the frame 2 and arranged for movement within the field produced by the coil is a core 4 of magnetic material. T 's core may be guided and arranged in any suitable manner, and as shown is provided with a pin 5 which extends into a hole'in'a lug 6 of magnetic material screwed into t e top of the frame 2'. The core .4 is extended at its lower end and on 'a reduced ortion 10 carries insulated therefrom a dis 1'1 of magnetic material such as steel. This 'disk 11 ma have a hub 12 of insulating material, the ole in which is somewhat larger than the extension 10 of the core 4, and this disk is normally held against, a shoulder formed by a larger portion 13 of the core 4 by means of a sprm 14 located between the insulating hub 12 o the disk 11 and .a collar 15 fixed upon the reto '19 through'ironwashers 24 and 25 and across I and 17 may be silver plated for a purpose hereinafter explained. Between the contacts 16 and 17 and the backplate 1 are located coils 18 and 19 of insulated wire, bolts of magnetic material 20 and 21 being arranged to clamp the contacts '16 and 17 to the coils 18 and'19 respectively, and to the base-plate 1 'in the manner clearly shown in Fig. 2. Brass washers 22'and 23 are clamped I tively, and terminals 26 and 27 are connected tosaid bolts.

, Mounted within the frame 2 is a second coil 30 of insulated wire, said coil being so 7 arranged that much of the magnetic fiux produced by the energization of the coil 3 will thread the coil 30. This coil is, therefore, inductively arranged with respect to coil 3 and will act as the secondary of a transformer ofwhich the coil 3 is the primary; that is, while the magnetic field produced by the coil 3 is building up or dying outcurrent will be induced in the coil 30.

The ends of this coil are connected respec-" tively to the terminals 31 and 32 which are also connected respectively to a terminal of the coil 18 and a terminal of the coil 19, the other ends of these coils being connected togcther at 33. It is apparent, therefore, that the coils 30, 18' and 19 are connected permanently in series. In the particular formor relay. shown the circuit through the coil 3 is from the terminal '35 to terminal 26, through bolt 20, fixed contact 16, movable contact diskll, fixed cont'act'17, bolt 21, terminal-27 to and through the coil 3 to the terminal 36. When so arranged the relay will in plulling up open its own actuating circuit. y invention, however, will be in no way affected if the circuit throu' h the coil 3 is altogether independent of t e contacts control ed by the relay, which contacts might be used to control some other circuit.-

. The operation of the device is as follows: The relay being in the position shown, when current is supplied to the coil 3 a magnetic field is produced into which the core .4 of the relay tends to rise. The core 4 will, therefore, pull up. While the magnetic field of the coil 3 is .building up, current will be induced in the coil 30 and will pass around the closed circuit formed by th1s coil and the coils 18 and .19! "This current will be suffi- V .cient to produce a magnetic -field, "the flux of which will pass from one of the steel contacts 16 or 17 to the other, through the steel a smallair' gap.

disk 11 and aroundbehind the coils 18 and s As long as this magnetic field exists. the disk 11 will beheld in contact with the fixed contacts 16 and 17 even though the core 13 pulls up, this being permitted by the compression of the spring 14; As soon as the fieldproduced by the coil 3 has become steady the current inducedinthe coil 30 diesout and the magnetic field produced by the coils 18 and 19, therefore, fades away. The disk 11 is then no longer held in engagement with the fixed contacts 16 and 17 and it flies upward under the action of the spring 14. operating surfaces of disk 11 and contacts "16 and '17 furnishes a gap in the magnetic field at these points andprevents sticking of the disk to the fixed contacts. The silver will also insure good contact between the disk and fixed contacts as is well understood.

What I claim as new and desire to secure by Letters Patent of the United States, is,-

1 In an electro-magnetically controlled switch, an actuating coil, a movable element magnetically controlled by said actuating coil, a second coil located in inductive relation to said actuating coil, and electro-magnetically controlled means receiving current from said second mentioned coil for retarding the operation of the switch in response to the energization of said actuating coil.

2. In an electro-magnetically controlled switch, an actuating coil, a movable element magnetically controlled by said actuating coil, contacts controlled by said movable element, a second coil located in inductive relation to said actuating coil, and electromagnetically controlled means receiving current from the second mentioned coil for retarding the relative movement of the contacts in response to the energizationof said actuatmg coil.

3. In'an electro-magnetically controlled switch, an actuating 001 a movable element magnetically" controlled by said actuating coil, contacts controlled by said movable element, a second coil located in inductive relation to said actuating coil, and electromagnetically controlled means including an actuating coil receiving current from the second mentioned coil for retarding the relative movement of the contacts in .respolnse to the energization of said actuating col 4. In an electro-magnctically controlled switch, an actuating coil, a movable element.

magnetically controlled by said; actuating coll, contacts of magnetic material controlled by said movable element, a second The silver on the co- I coil located in inductive relation to said ac tuatingcoil, and a coil receiving current from the second mentioned coil and arranged to produce a magnetic field through said contacts.

6.-In an electro-magnetically operated switch, an actuating coil, a movable element magnetically operated by said actuating coil, a second coil located in inductive relation to said actuating coil, and electro-magnetically controlled means receiving current from said second mentioned coil -for-retarding the operation of theswitch in response to the energization of said actuating coil.-

7. In ,an electro-magnetically operated switch, an actuating co1l,.a mova le ele- 'mentmagnetically operated by said actuating coil, contacts opened and closed by the movement of said movable element, a second coil located in inductive relation to said actuating coil, and 'electro-magnetically operated means receiving current from the second mentioned coil for retarding the relative movement of the contacts in response to the energization of said actuating coil.

8. In an electro-magnetically operated switch, an actuating coil, a movable element magnetically actuated by said actuating coil, contacts opened and closed by movement of said movable element, a second coil located in inductive relation to said actuating coil, and electro-m'agnetically operated means including an actuating coil receiving current from the second mentioned coil for retarding the relative movement of the contacts in response to the energization of said actuating coil. 7

9. In an electro-magnetically operated switch, an actuating coil, a movable element magnetically operated by said actuati-ng coil, contacts opened and closed by.

movement of said movable element, a second coil located in inductive relation to said actuating coil, and electro-magnetically actuated means including an actuating coil arranged in series with said last mentioned coil for retarding the relative movement of the contacts in response to the energization of said actuating coil.

' 10. In an electro-magnetically o erated switch, an actuating coil, a mova le'element magnetically operated by said actuating coil, contacts of magnetic material opened and closed by movement of said movable element, a second coil located in inductive relation to said actuating, coil, and a. coil receiving current from said second mentioned coil and arranged to produce a magnetic field through said contacts.

11'. In an elcctroemagnetically operated switch, an actuating coil, a core of magnetic material arranged for movement in the field thereof, a movable contact member movable with said core, a stationary contact with which said movable contact member co operates, a second coil located in inductive relation to said actuating coil, and electromagnetically controlled means including an actuating coil receiving current from the second mentioned coil for retarding the relative movement of the contacts in response to the energization of said actuating coil. r

12. In an electro-magnetically operated switch, an actuating coil, a core of magnetic material arranged for movement in the field thereof a movable contact member of ma i D netic material movable with said core, a stationary contact of magnetic material with which said'movable contact member cooperates, a second coil located in inductive relation to said actuating coil, and a coil receiving current from the'second mentioned coil and arranged to reduce a magnetic field through said mova le contact member and said stationary contact.-

13. In an electro-magnetically operated switch, an actuating coil, a core of magnetic material arranged for movement in the field by said core and movable thereon, a spring.

tending to kee said disk in a certain position on said core, ixedcontacts of magnetic material with which said disk is in engagement when said actuating coil is deenergized, a second coii iocated in induct ve relation to said actuating coil, and coils receiving current from the second mentioned coil and arranged to produce a magnetic field through said fixed contacts and said movable contact member.

In witness whereof, I have hereunto set my hand this 27th day of March, 1908.

ARCHIBALD S. CUBITT.

Witnesses: I

HELEN @RFORD, L. A. HAWKINS. 

